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When all else fails, read the source

Joined: 24 Aug 2004
Posts: 20210
Location: In your JS exploiting you and your system
revolution 30 Sep 2008, 01:45
tom tobias wrote:
Anyone can write "fastest code on the planet..."
If you say your code is faster then prove it. I have yet to see any other code that can do a faster FFT. Many others have written code and hoped it to be faster but still no one has managed to even match the performance.
tom tobias wrote:
Seriously, how many points are there in these FFT's?
2560k, just what I wrote.The code currently can test numbers up to ~2^593M using a larger FFTs as needed.
tom tobias wrote:
Why is it useful, i.e. why does someone or something give 100K$ for discovery of a prime number ...
If you go to the EFF website you will see that the prize is intended to promote distributed computing, the actual number is not important and AFAIK there is currently no practical uses for primes of this size.
Post 30 Sep 2008, 01:45
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Joined: 21 Jul 2003
Posts: 3976
Location: vpcmipstrm
bitRAKE 30 Sep 2008, 05:22
A bit sieve is very fast to generate and access:
    mov edi,sieve 
    xor ecx,ecx 
.0: bt [edi],ecx 
    inc ecx 
    jnc .0 
    ; ECX*2 + 1 is prime number (P) 
    lea eax,[ecx*2+2] 
    mul ecx ; (P+1)*(P-1)/2 
    dec eax 
    ; exit if out of range 
    cmp eax,MAX_BITS 
    jnc .x 
    ; clear bits representing odd multiples of (P) 
.1: btr [edi],eax 
    lea eax,[eax+ecx*2+1] 
    cmp eax,MAX_BITS 
    jc .1 
    jmp .0 

MAX_BITS = 1 shl 24 
; if bit(n) then (2*n+3) is prime 
sieve db MAX_BITS/8 dup (-1) 

...once the table is created only a single instruction is needed to test an odd number for primeness. For some algorithms this can be very beneficial.

¯\(°_o)/¯ “languages are not safe - uses can be” Bjarne Stroustrup
Post 30 Sep 2008, 05:22
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Joined: 16 Oct 2009
Posts: 23
SolidThink 16 Oct 2009, 16:07
help me ! Wink

I set

PSELEND = 17894471

I would start the program automatically unless the push button start,
but do not understand where I have to make code changes.
: Cry:

simplifying ....

to do a single loop with PSELEND = 17894471
and then exits automatically when calculation has finished.

it's possible ?

;cmp [wparam],BN_CLICKED shl 16 + ID_START
;je btnnone

this code run "START" ?
Post 16 Oct 2009, 16:07
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